If necessary, put the chicken on a cutting board and use a sharp knife to cut it into bite-size pieces.
Pour the cooking oil into a skillet. Put the skillet on a burner. Turn burner to mediun-high heat. Heat oil. You can tell when the skillet is hot enough by sprinkling a couple drops of water into the skillet. When the water drops dance on the surface, it is time to add the chicken. Add chicken to skillet; cook about 6 minutes or until chicken pieces are no longer pink, stirring chicken all the time with a wooden spoon. Add vegetables to the skillet. Cover skillet with lid. Cook for 5 to 7 minutes or until vegetables are tender but still slightly crunchy.
While vegetables are cooking, open the can of pineapple, using a can opener if necessary. Open the packages of noodles. Break each block of noodles into small pieces in a bowl. Throw away seasoning packets.
Add pineapple chunks and juice, noodles, stir-fry sauce, and water to the vegetables and chicken in the skillet. Use the wooden spoon to stir until the liquid covers all of the pieces. Bring to boiling; turn heat to medium-low heat. Cover and cook about 3 minutes or until noodles are tender, stirring now and then with wooden spoon.
Serve with fresh mango slices, chocolate cake for dessert, and milk.